Valve prosthesis

Abstract

Heart valve prostheses are provided having a self-expanding frame that supports a valve body comprising a skirt and a plurality of coapting leaflets. The leaflets are constructed with four commissure points to reduce the stress and strain applied to the commissure points and to efficiently distribute and transmit forces along the leaflets and to the frame.

What is claimed is: 
     
       1. A valve prosthesis comprising:
 a valve body including a first leaflet, a second leaflet, a third leaflet, and a fourth leaflet; and 
 a self-expanding frame, 
 wherein the first leaflet is attached to the second leaflet at a first commissure point, the second leaflet is attached to the third leaflet at a second commissure point, the third leaflet is attached to the fourth leaflet at a third commissure point, the fourth leaflet is attached to the first leaflet at a fourth commissure point, 
 wherein the first, second, third and fourth commissure points are sewn to the frame, 
 wherein a first angle is formed between the first commissure point and the second commissure point with a vertex of the first angle being a center of the frame, a second angle is formed between the second commissure point and the third commissure point with a vertex of the second angle being the center of the frame, a third angle is formed between the third commissure point and the fourth commissure point with a vertex of the third angle being the center of the frame, and a fourth angle is formed between the fourth commissure point and the first commissure point with a vertex of the fourth angle being the center of the frame, such that the vertex of each of the first, second, third and fourth angles are at the center of the frame, and 
 wherein the second angle and the fourth angle are each approximately 170 degrees and are greater than the first angle and the third angle. 
 
     
     
       2. The valve prosthesis according to  claim 1 , wherein the first angle and the third angle are approximately equal. 
     
     
       3. The valve prosthesis according to  claim 1 , wherein a first free portion of the first leaflet and a first free portion of the second leaflet form a first coaptive edge, a second free portion of the second leaflet and a first free portion of the third leaflet form a second coaptive edge, a second free portion of the third leaflet and a first free portion of the fourth leaflet form a third coaptive edge, a second free portion of the fourth leaflet and a second free portion of the first leaflet form a fourth coaptive edge, and a third free portion of the first leaflet and a third free portion of the third leaflet form a fifth coaptive edge, and
 wherein the fifth coaptive edge is greater in length than each of the first, second, third, and fourth coaptive edges, 
 wherein the first, second, third, and fourth commissure points are disposed longitudinally offset from the first, second, third, fourth and fifth coaptation edges. 
 
     
     
       4. The valve prosthesis according to  claim 3 , wherein the first, second, third, and fourth coaptive edges are approximately equal in length.